This complete upper includes our new ATLAS S-ONE Handguard! The S-ONE line of handguards are designed with size and weight in mind, providing the perfect addition to your lightweight build. Our proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards.

Includes:

M4E1 Threaded Assembled Upper Receiver

ATLAS S-ONE Handguard of choice

14.7" 5.56 Mid Pencil Length Barrel

Low Profile Gas Block and Mid Pencil Length Gas Tube

Product comes assembled

This complete upper does not include BCG or Charging Handle. These products may be selected as add-ons under the Finish Your Build tab

The muzzle brake that comes with this complete upper receiver is NOT pinned nor welded to this barrel. Per the National Firearms Act, the muzzle brake MUST be pinned and welded to achieve the necessary 16" as defined by the ATF for a rifle build.

M4E1 Threaded Upper Receiver Features:

New enhanced forging that gives the upper receiver a "billet look"

New picatinny profile that blends seamlessly with our Enhanced Series Handguards